U.S. Attorney General Jeff Sessions said Monday that parents who enter the country illegally with children can expect to be arrested and prosecuted for illegal entry, and separated from their sons and daughters.Family separations have already been occurring informally, but now it's federal policy, and more arrests can be expected.

One reason officials cite for the crackdown is what they describe as widespread smuggling of minors into the U.S., which immigrant advocates dispute. Instead, they see the threat of separating parents from children as the Trump administration's attempt to discourage illegal border crossings.

Here's what these latest development on immigration means for Southern California.

Do we know how many children are coming across the U.S.-Mexico border, and is the number growing?

According to immigration officials, there has been an uptick recently in the number of unaccompanied minors and also in the number of family units — that's parents with children.

Officials said in April, there was an 8 percent increase in the number of families and a 2 percent hike in minors traveling by themselves. And they said overall border arrests have spiked sharply in the past couple of months, compared with a year ago.

Since October, the start of the federal fiscal year, there have been 26,000 unaccompanied minors and 49,000 families caught by the border patrol officers.

U.S. Customs and Border Protection also track a category of people they call "inadmissibles"who show up seeking legal admission and don’t have the proper documents, including those seeking asylum. Since October, about 4,600 of these have been unaccompanied minors, and about 24,000 have been families.

Although there has been an increase lately, border arrests are still historically low. There were about 300,000 last year, compared to three times that a decade ago. In the mid-2000s, arrests at the southern border topped a million a year.

Do many of the families choose to live in Southern California?

Yes. In recent years, there has been a big increase in the number of Central Americans arriving at the border who say they are fleeing gang violence and instability and seeking asylum. A major wave of unaccompanied minors arrived a few years back; now more families are coming.

There is a very large Central American community in the Los Angeles area, and many of these families are bound for Southern California, hoping to be reunited with family members here.

Is it true, as federal officials say, that many parents pay smugglers to take their children over the border?

This has long been a common practice.

While it’s true that many families can’t afford it, and families and children will makethe dangerous crossing through Mexico on their own, those who can pay someone to guide them, will do so.

Sometimes payment comes from a parent who is desperate to send their children away from the gangs that control their community in Central America. Or it can be a family member in the U.S., who has deeper pockets and can afford it.

While smugglers exploit the situation, families may see a smuggler as someone who can lead them or their loved ones out of a bad situation to freedom or safety, or to better opportunities in the U.S.

Attorney General Sessions said: “If you are smuggling a child, then we will prosecute you, and that child will be separated by you.” What will this mean for families?

Sessions stated that parents caught crossing the border illegally would be sent to federal court and prosecuted for illegal entry, and their children separated from them.

But the statements raise the question whether parents would be subject to prosecution for smuggling their children into the country.

A U.S. Department of Homeland Security spokeswoman told KPCC Tuesdaythat if it’s a legitimate family that is crossing the border illegally, the parents would be prosecuted for illegal entry, not for smuggling.

Still, the parents and children would be separated. The children would be sent into the care of the U.S. Department of Health and Human Services, which would place them in a shelter until they can locate a relative or sponsor in the U.S. with whom they can live.

Does the Sessions' "zero tolerance policy" apply to asylum seekers?

Sessions said, “If you cross this border unlawfully, we will prosecute you.” But he didn’t add, “if you present yourself to an immigration officer,” which is what asylum seekers typically do. Sessions talked of fraudulent asylum claims amounting to felonies, but he did not specifically mention prosecuting asylum seekers.

According to Homeland Security, asylum seekers who present themselves at a port of entry will not be prosecuted, and they will be interviewed to determine if they have reason to seek protection, as is the process now. If they have children, the family will be placed in family detention but not separated.

However, there have been recent cases of asylum seekers who were separated.

In one recent case, a 7-year-old girl was taken from her Congolese mother in San Diego and the child sent to the Midwest. Homeland Security would not comment on the case, saying it’s in litigation.

A legal group that represents child migrants said it has recently handled cases in which children were separated from parents who were not only crossing illegally, but also seeking asylum.

The New York Times reported recently that as many as 700 children have been separated from their parents at the border in recent months.

What are the immigrant advocates saying about this latest move by the Trump administration?

Jennifer Podkul is policy director for Kids in Need of Defense, or KIND, which represents migrant kids in immigration court pro-bono.

“Saying that the reason why they are separating people is to try to protect against traffickers is disingenuous and is not the real issue here,” Podkul said.

She said she believes the Trump administration is generally suspicious "of anyone who is coming to ask for protection in the United States."

Homeland Security officials say children are being used by “bad actors” in order to gain entry. They provide examples – three from last year and one from 2016 – involving Honduran nationals in which adults unrelated to the child tried to gain entry fraudulently by claiming they were relatives.

Those who work with immigrant children and families say this is not the norm, and that the vast majority of the families are coming for legitimate reasons. They claim that the Trump administration is announcing these policies to keep them from trying.

The Washington Post reported Wednesday that the Trump administration is considering new regulations that would affect how families and children are detained, including possibly detaining families for longer periods, and making it easier to separate families if it's too difficult to detain them together.